Renewable energy is on the rise.Solar power and wind power are on the rise.When combined with conventional fossil fuel thermal power generation, DR demand response is required.In other words, there is a need to temporarily store excess electricity generated in storage batteries.
https://xtech.nikkei.com/atcl/nxt/column/18/02443/120400029/
Installed stationary storage batteries for this application do not need the lightweight, high-density performance of EVs.They need only to be cheap, safe, and able to be repeatedly recharged and discharged.
They should be installed in close proximity to wind and solar power generation sites.Sensors would check the amount of electricity generated and stored in these batteries, and discharge them at optimal times according to the overall supply and demand of electricity.
Air batteries that can be charged and discharged are needed to meet the needs of these stationary storage batteries.
Although alkaline electrolytes provide higher output for air batteries, weakly acidic electrolytes are easier to handle from a safety standpoint.
Electrodes that dissolve in mildly acidic solution, such as wood vinegar, can be made from metals with ionization tendencies lower than those of iron.Lithium is dangerous, so air batteries are made of metals such as sodium, magnesium, zinc, aluminum, and iron.
Aluminum and zinc are a little more difficult to use for charge-discharge cycle characteristics.Iron is a common and safe metal, and there is much room for improvement in combination with phosphoric acid and sulfur.
We would like to realize an iron-air battery with safe and commonplace materials such as gel, earth, sand, and wood vinegar solution.
The goal of the iron-air battery is, above all, its cycle characteristics.Currently, the cycle time is several dozen times, but we would like to increase it to 1,000 times.We would like to achieve this goal by using creative materials.
再生エネルギーが増えている。太陽光発電や風力発電だ。従来の化石燃料の火力発電と組み合わせるときにはDRデマンド レスポンスが必要になる。つまり発電し過ぎた電力を蓄電池に一時的に貯めておくニーズがある。
https://xtech.nikkei.com/atcl/nxt/column/18/02443/120400029/
この用途の設置据え置き型蓄電池はEVのような軽量高密度の性能は不要だ。安くて安全に繰り返し充放電できれば良い。
風力発電や太陽光発電の設置場所の近くに併設する。そうした発電量と蓄電池をセンサでチェックして、全体の電力需給に合わせて最適な時間帯に放電する仕組みだ。
こうした据え置き型蓄電池のニーズに応えるために充放電できる空気電池は必要とされている。
空気電池はアルカリ性の電解質のほうが高出力だが、安全性の面では弱酸性が扱いやすい。
木酢液程度の弱酸性で溶解する電極なら、イオン化傾向で鉄より卑な金属から選べる。リチウムは危険だからナトリウム、マグネシウム、亜鉛、アルミニウム、鉄あたりの金属の空気電池だ。
充放電のサイクル特性を考えるとアルミニウム、亜鉛は少し難しい。鉄はありふれた安全な金属で、リン酸や硫黄との組み合わせで改善の余地も大きい。
鉄空気電池をゲルや土砂、木酢液という安全でありふれた素材で実現させたい。
鉄空気電池の目標は何と言ってもサイクル特性だ。現状は数十回レベルだが1000回にしたい。そこを素材で工夫して実現させたい。